#set terminal x11
set parametric
set pm
#set palette rgbformulae 33,13,10  # for rainbow color
#set palette rgbformulae 22,13,-31 
set cbrange [0:8]
#set view 0, 90
set view map
set size ratio 1.0
unset surface
unset contour
set cntrparam levels 40
set zero 0
splot 'show_boundary' u 2:1:3 w l  # for material id of ey 
#splot 'show_boundary' u 2:1:4 w l # for material id of ez